chore(release): update unreleased CHANGELOG versions (#16911)

FirebaseABTesting/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [fixed] Improved robustness when parsing malformed experiment payloads from
   the server. (#16728)
 - [fixed] Fixed an issue where Remote Config's `activate()` completion could be

FirebaseAI/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [feature] **Public Preview**: Added `SpeechMetadata` support to `TextPart`
   for Gemini text-to-speech (TTS) models, enabling turn-level speaker routing
   in multi-speaker synthesis and sustained speech delivery styling. See the

FirebaseAuth/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [fixed] Fixed a bug in URL domain validation and improved keychain logging safety.
 - [changed] Strengthened the randomness and length of generated OAuth and reCAPTCHA session identifiers.
 - [fixed] Fixed a crash by safely skipping malformed account provider

FirebaseDatabase/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [fixed] Fixed a potential crash at every launch after the server sent an
   invalid database host. Such hosts are now ignored, and a saved one is
   discarded. (#16863)

FirebaseFunctions/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [fixed] Fixed callable streams failing with "Unexpected format for streamed
   response." when the server sends SSE comment lines, such as the `: ping`
   heartbeat emitted during long-running streaming functions. (#16605)

FirebaseMessaging/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [fixed] Reduced main-thread work when setting the APNs token: the APNs
   environment check no longer queries the App Store receipt, and the keychain is
   read once instead of up to twice. (#16726)

FirebaseRemoteConfig/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [fixed] Fixed a crash when the Remote Config fetch response contains a
   non-dictionary top-level JSON object (such as a JSON array). (#16735)
 - [fixed] Fixed crashes when nested fields of a fetch response (such as `state`,

FirebaseStorage/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 13.1.0
 - [fixed] Fixed a race where an observer added while an upload or download task was completing
   could be called twice for the success or failure event. This could crash `putDataAsync`,
   `putFileAsync`, and `writeAsync` when called with an `onProgress` handler. (#16813)